BARCELONA forward Lionel Messi will miss his side's Champions League match with Celtic after picking up a hamstring injury which will rule him out of action for the next two months.

Messi limped off 21 minutes into Barca's 4-1 win over Real Betis on Sunday after injuring his left hamstring and he underwent further tests today to determine the extent of the problem.

After receiving the results, Barcelona said the Argentinian is likely to be absent for between "six and eight weeks".

Barca are already through to the knockout stages of the Champions League but Celtic's own qualification hopes will be boosted with the news that the influential playmaker will miss his side's remaining group matches.

The La Liga giants face a trip to Ajax at the end of this month before taking on Neil Lennon's side in the final group game on December 11.

Celtic will be looking to win their final two matches against AC Milan and Barcelona to give themselves any realistic chance of progressing to the final 16.

A Barca statement read: "According to the club's medical services, the tests taken on Monday morning by Leo Messi have confirmed that the player has suffered a torn muscle in the femoral biceps of his left leg.

"The approximate time he will be out is between six and eight weeks.

"The first part of his recovery will take place in Barcelona and the second, in Buenos Aires."

The world player of the year, 26, has suffered hamstring problems twice already this season.

His team-mate Cesc Fabregas, who experienced similar problems while at Arsenal, has urged Messi not to try to rush his recovery.

He said: "He needs to take as much time as he needs to recover and get back to his level. We need him at his best.

"I had something similar at Arsenal. You think you're okay, but you're not.

"I had this injury, I wasn't right for up to a year and half, it's a really frustrating injury.

"You need to take whatever time you need because if you don't it won't heal properly."